The battle of Utica (49 BC) was an initial victory won by G. Scribonius, Caesar's commander in North Africa, over Pompey's supporters (Great Roman Civil War).
While Caesar led his main army into Spain, G. Scribonius Curio was given command of four legions that were to secure Sicily and North Africa. Some of these legions had only recently changed sides, having surrendered to Caesar at Corfinium during his march on Rome, and their loyalty was thus suspect.
The Pompeian forces in North Africa were commanded by P. Attius Varus. He had two legions at Utica and a third at Hadrumentum, and also had the support of King Juba of Numidia, who had a personal grudge against both Caesar and Curio.
Curio quickly secured Sicily, and then led two of his legions and 500 cavalry across to North Africa. Curio landed somewhere close to Cape Bon (near Clupea, modern Kelibia). He then advanced around what is now the Gulf of Tunis, reaching the Bagradas River after two days. In ancient times this river flowed into the sea just to the south of Utica, which was then a coastal city.
Curio ordered his legions to stop at the river and then led his cavalry towards Utica, to investigate the possibility of using the Cornelian camp as his own base. This rocky headland had been used by Publius Cornelius Scipio Africanus during his siege of the city 150 years earlier, and was around one mile from the city as the crew flies.
After looking at this position Curio continued on to examine the city. Varus was camped just outside the city, in a strong position close to the city walls and protected by the suburbs and a nearby theatre. During this reconnaissance Curio ambushed a supply column, dispersing a force of Numidian cavalry and capturing the stores. At about the same time his fleet reached the city, and intimidated around 200 merchant ships into sailing to the Cornelian Camp.
After this successful raid Curio moved his entire army up to Utica, and began to build a camp. While his men were working on the camp news reached him that fresh troops from King Juba were close by, marching to join the garrison of Utica. Curio responded by sending his cavalry to attack the Numidians, who were caught by surprise. The Numidian cavalry managed to escape into the town, but their infantry suffered some heavy losses.
On the following night two of Curio's centurions, former members of the legions that had changed sides at Corfinium, deserted and fled into Utica. They convinced Varus that the rest of Curio's army would also change sides if given the chance, and so on the following morning Varus led his legions out of their camp and formed up ready for battle. Curio did the same and the two armies faced each other across a narrow valley. Some of Varus's men were able to mingle with their opponents, creating something of a sense of paranoia amongst Curio's officers, but the legions remained loyal and both armies retreated into their camps. After a council of war Curio made a speech to his troops which Caesar claims secured their loyalty. He then decided to seek out battle on the next possible occasion.
On the following day both armies formed up again, with the same valley between them. This difficult ground meant that whichever army moved first would be at a serious disadvantage. Varus acted first, sending his cavalry and some light infantry to attack Curio's left wing. Curio responded by sending his own cavalry and two cohorts of infantry. Varus's men were defeated, the cavalry fled and the light infantry massacred. Curio took advantage of this by leading his men in an attack on Varus's line. Discouraged by the defeat of their cavalry, Varus's men turned and fled back into Utica and their camp.
According to Caesar's account Varus lost around 600 dead and 1,000 wounded, most in the crush to get back into the city and the rest in the cavalry fight. He doesn't give casualty figures for the cavalry fight, but claimed that only one of his men was killed during the main part of the battle, one Fabius who got ahead of the rest of the army and nearly killed Varus before being cut down. This would suggest that the difficult ground between the two armies slowed Curio's men down so much that they were unable to catch up with their opponents.
Although Varus had managed to keep control of his fortified camp in the immediate aftermath of the battle, most of his wounded men moved into the city. This forced Varus to abandon his camp, and move all of his men into Utica.
On the day after this battle Curio decided to besiege Utica. Only the news that King Juba was on his way with a relief army prevented the citizens from surrendering to Curio, who was thus forced to begin a regular siege. This was a short-lived affair, and ended when Curio learnt that Juba was on his way. Curio withdrew to the Cornelian Camp, but after receiving false information about Juba's strength advanced out to attack, suffering a catastrophic defeat at the battle of the Bagradas River (24 July 49 BC).